international development for aid use only bibliographic input sheet

38
A(ENCY FOR INTERNATIONAL DEVELOPMENT FOR AID USE ONLY WASHINGTON, 0. C. 20523 BIBLIOGRAPHIC INPUT SHEET A. PRIMARY I, SUBJECT Agriculture AP12-0000-G730 CLASSI- B. SECONDARY FICATION Drainage and irrigation--Pakistan 2. TITLE AND SUBTITLE Dye dilution method of discharge measu,:ement 3. AUTHOR(S) LiangW.S.; Richardson,E.V. 4. DOCUMENT DATE 5. NUMBER OF PAGES 6. ARC NUMBER ARC 1971 I 3 1p. PK631.62.L693 7. REFERENCE ORGANIZATION NAME AND ADDRESS Colo. State 8. SUPPLEMENTARY NOTES (Sponsorlng Organizatlon, Publilahers, Availability) (InWater management tech.rpt.no.3) 9. ABSTRACT 10. CONTROL NUMBER 11. PRICE OF DOCUMENT PN-RAA-Tir5 12. DESCRIPTORS 13. PROJECT NUMBER Canals Flow measurement 14. CONTRACT NUMBER Fluorescent dyes CSD-2162 Res. Pakistan 15. TYPE OF DOCUMENT Seepage AID 590°1 14°74)

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Page 1: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

A(ENCY FOR INTERNATIONAL DEVELOPMENT FOR AID USE ONLY WASHINGTON 0 C 20523

BIBLIOGRAPHIC INPUT SHEET A PRIMARY

ISUBJECT Agriculture AP12-0000-G730CLASSI-

B SECONDARYFICATION Drainage and irrigation--Pakistan

2 TITLE AND SUBTITLE

Dye dilution method of discharge measuement

3 AUTHOR(S)

LiangWS RichardsonEV

4 DOCUMENT DATE 5 NUMBER OF PAGES 6 ARC NUMBER

ARC1971 I 31p PK63162L693 7 REFERENCE ORGANIZATION NAME AND ADDRESS

ColoState

8 SUPPLEMENTARY NOTES (Sponsorlng Organizatlon Publilahers Availability)

(InWater management techrptno3)

9 ABSTRACT

10 CONTROL NUMBER 11 PRICE OF DOCUMENT

PN-RAA-Tir5 12 DESCRIPTORS 13 PROJECT NUMBER

Canals Flow measurement 14 CONTRACT NUMBER

Fluorescent dyes CSD-2162 Res Pakistan 15 TYPE OF DOCUMENT

Seepage AID 590deg1 14deg74)

DYE DILUTION METHOD OF DISCHARGE MEASUREMENT

Water Management Technical Report No 3

by

W SLiang

and E V Richardson

Prepared under support of

United States Agency for International DevelopmentContract No AIDcsd-2162Water Management Research

inArid and Sub-Humid Lands of the Less Developed Countries

Engineering Research Center Colorado State University Fort Collins Colorado

January 1971

CER70-71 WSL-EVR47

Reports published previously in this series are listed below Copies can be obtained by contacting Mrs Mary Fox Engineering Research CenterColorado State University Fort Collins Colorado 80521

ReportNo Date Title Authors Cost

1 Sept 1969 Bibliography with annotations KMahmood $300 on Water Diversion Conveyance A G Mercer and Application for Irrigation E V Richardson and Drainage CER69-70KM3

2 May 1970 Organization of Water P0 Foss $1480 Management for Agricultural J A Straayer Xerox Production inWest Pakistan R Dildine copies(a Progress Report) ID 70- A Dwyer only 71-1 R Schmidt

FORWARD

This is the third technical report of a series of water management

research reports published by Colorado State University (CSU) The

report Dye Dilution Method of Discharge Measurement was supported

by funds provided by the US Agency for International Development

(AID) contract csd-2162 Water Management Research inArid and Sub-

Humid Lands of the Less Developed Countries The Water Management

Research Project isan interdepartmental effort by CSU involving the

Departments of Agricultural Engineering Agronomy Civil Engineering

Economics Political Science and Sociology

Concern of AIDWashington about the worlds agricultural production

led AID to foster the cooperation of several universities to work on research to improve water management for increased agricultural production

A consortium of universities consisting of the University of Arizona CSU

University of California at Davis and Utah State University called The

Council of United States Universities for Soil and Water Development in

Arid and Sub-Humid Areas (CUSUSWASH) was formed on May 12 1967 The

University of Arizona joined the consortium inOctober 1969 The general

chairman of CUSUSWASH isA R Chamberlain President of CSU The

Director of the Water Management Research Project at CSU isMaurice L

Albertson Professor-in-charge of the Water Resource Systems Engineering

Program inCivil Engineering

The Project has as its field of study the management of water for

the optimum development of agriculture inarid areas with special refershy

ence to the Indus Basin of Pakistan The main purposes of the Project

are to aid Pakistan and other arid and sub-humid areas in solving their

water management problems with respect to increased food production and

to cooperate with Pakistani centers of study to help them develop their

research capabilities in the areas of water management

The study reported herein on Dye Dilution Method of Discharge

Measurement was undertaken to provide information on a method of

measuring and tracing water seeping from canals Previous studies at

CSU indicated that flourescent dyes could be accurately determined at

the parts per billion level The techniques developed during this study

should be useful infuture tubewell water supply and drainage studies to

be conducted in Pakistan

ii=

ACKNOWLEDGMENTS

This report was prepared by Mr W S Liang and Professor E V

Richardson of the Civil Engineering Department with the support of the

United States Agency for International Development via Contract No AID

csd-2162 Water Management Research in Arid and Sub-Humid Lands of the

Less Developed Countries The Water Management Project at CSU falls

under the general auspices of the Council of United States Universities

of Soil and Water Development in Arid and Sub-Humid Areas consisting of

the University of Arizona Colorado State University University of

California at Davis and Utah State University

iii

TABLE OF CONTENTS

FORWARD

ACKNOWLEDGMENTS

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

INTRODUCTION l 1

THEORY 1 EQUIPMENT REQUIRED 4

a Dye solution injection equipment 4

1 Mariotte vessel 4 2 Aerofeed chemical dispenser 5

b Measurement of dye concentration 5 c Samplers and containers 6 d Temperature control apparatus 6

PROCEDURE 7

a Preparation of standard solution 7 b Fluorometer calibration 8 c Preparation of injection dye solution 9 d Selection of injection rate q 10 e Injection and sampling O10 f Sample analysis and discharge computation 12

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE 13

a njection rate 13 b Sample analysis 13 c Concentration of the injected dye solution 13 d Discharge computation 13

BIBLIOGRAPHY 15

APPENDIX 16

TABLES 17

FIGURES 22

iv

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 2: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

DYE DILUTION METHOD OF DISCHARGE MEASUREMENT

Water Management Technical Report No 3

by

W SLiang

and E V Richardson

Prepared under support of

United States Agency for International DevelopmentContract No AIDcsd-2162Water Management Research

inArid and Sub-Humid Lands of the Less Developed Countries

Engineering Research Center Colorado State University Fort Collins Colorado

January 1971

CER70-71 WSL-EVR47

Reports published previously in this series are listed below Copies can be obtained by contacting Mrs Mary Fox Engineering Research CenterColorado State University Fort Collins Colorado 80521

ReportNo Date Title Authors Cost

1 Sept 1969 Bibliography with annotations KMahmood $300 on Water Diversion Conveyance A G Mercer and Application for Irrigation E V Richardson and Drainage CER69-70KM3

2 May 1970 Organization of Water P0 Foss $1480 Management for Agricultural J A Straayer Xerox Production inWest Pakistan R Dildine copies(a Progress Report) ID 70- A Dwyer only 71-1 R Schmidt

FORWARD

This is the third technical report of a series of water management

research reports published by Colorado State University (CSU) The

report Dye Dilution Method of Discharge Measurement was supported

by funds provided by the US Agency for International Development

(AID) contract csd-2162 Water Management Research inArid and Sub-

Humid Lands of the Less Developed Countries The Water Management

Research Project isan interdepartmental effort by CSU involving the

Departments of Agricultural Engineering Agronomy Civil Engineering

Economics Political Science and Sociology

Concern of AIDWashington about the worlds agricultural production

led AID to foster the cooperation of several universities to work on research to improve water management for increased agricultural production

A consortium of universities consisting of the University of Arizona CSU

University of California at Davis and Utah State University called The

Council of United States Universities for Soil and Water Development in

Arid and Sub-Humid Areas (CUSUSWASH) was formed on May 12 1967 The

University of Arizona joined the consortium inOctober 1969 The general

chairman of CUSUSWASH isA R Chamberlain President of CSU The

Director of the Water Management Research Project at CSU isMaurice L

Albertson Professor-in-charge of the Water Resource Systems Engineering

Program inCivil Engineering

The Project has as its field of study the management of water for

the optimum development of agriculture inarid areas with special refershy

ence to the Indus Basin of Pakistan The main purposes of the Project

are to aid Pakistan and other arid and sub-humid areas in solving their

water management problems with respect to increased food production and

to cooperate with Pakistani centers of study to help them develop their

research capabilities in the areas of water management

The study reported herein on Dye Dilution Method of Discharge

Measurement was undertaken to provide information on a method of

measuring and tracing water seeping from canals Previous studies at

CSU indicated that flourescent dyes could be accurately determined at

the parts per billion level The techniques developed during this study

should be useful infuture tubewell water supply and drainage studies to

be conducted in Pakistan

ii=

ACKNOWLEDGMENTS

This report was prepared by Mr W S Liang and Professor E V

Richardson of the Civil Engineering Department with the support of the

United States Agency for International Development via Contract No AID

csd-2162 Water Management Research in Arid and Sub-Humid Lands of the

Less Developed Countries The Water Management Project at CSU falls

under the general auspices of the Council of United States Universities

of Soil and Water Development in Arid and Sub-Humid Areas consisting of

the University of Arizona Colorado State University University of

California at Davis and Utah State University

iii

TABLE OF CONTENTS

FORWARD

ACKNOWLEDGMENTS

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

INTRODUCTION l 1

THEORY 1 EQUIPMENT REQUIRED 4

a Dye solution injection equipment 4

1 Mariotte vessel 4 2 Aerofeed chemical dispenser 5

b Measurement of dye concentration 5 c Samplers and containers 6 d Temperature control apparatus 6

PROCEDURE 7

a Preparation of standard solution 7 b Fluorometer calibration 8 c Preparation of injection dye solution 9 d Selection of injection rate q 10 e Injection and sampling O10 f Sample analysis and discharge computation 12

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE 13

a njection rate 13 b Sample analysis 13 c Concentration of the injected dye solution 13 d Discharge computation 13

BIBLIOGRAPHY 15

APPENDIX 16

TABLES 17

FIGURES 22

iv

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 3: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

Reports published previously in this series are listed below Copies can be obtained by contacting Mrs Mary Fox Engineering Research CenterColorado State University Fort Collins Colorado 80521

ReportNo Date Title Authors Cost

1 Sept 1969 Bibliography with annotations KMahmood $300 on Water Diversion Conveyance A G Mercer and Application for Irrigation E V Richardson and Drainage CER69-70KM3

2 May 1970 Organization of Water P0 Foss $1480 Management for Agricultural J A Straayer Xerox Production inWest Pakistan R Dildine copies(a Progress Report) ID 70- A Dwyer only 71-1 R Schmidt

FORWARD

This is the third technical report of a series of water management

research reports published by Colorado State University (CSU) The

report Dye Dilution Method of Discharge Measurement was supported

by funds provided by the US Agency for International Development

(AID) contract csd-2162 Water Management Research inArid and Sub-

Humid Lands of the Less Developed Countries The Water Management

Research Project isan interdepartmental effort by CSU involving the

Departments of Agricultural Engineering Agronomy Civil Engineering

Economics Political Science and Sociology

Concern of AIDWashington about the worlds agricultural production

led AID to foster the cooperation of several universities to work on research to improve water management for increased agricultural production

A consortium of universities consisting of the University of Arizona CSU

University of California at Davis and Utah State University called The

Council of United States Universities for Soil and Water Development in

Arid and Sub-Humid Areas (CUSUSWASH) was formed on May 12 1967 The

University of Arizona joined the consortium inOctober 1969 The general

chairman of CUSUSWASH isA R Chamberlain President of CSU The

Director of the Water Management Research Project at CSU isMaurice L

Albertson Professor-in-charge of the Water Resource Systems Engineering

Program inCivil Engineering

The Project has as its field of study the management of water for

the optimum development of agriculture inarid areas with special refershy

ence to the Indus Basin of Pakistan The main purposes of the Project

are to aid Pakistan and other arid and sub-humid areas in solving their

water management problems with respect to increased food production and

to cooperate with Pakistani centers of study to help them develop their

research capabilities in the areas of water management

The study reported herein on Dye Dilution Method of Discharge

Measurement was undertaken to provide information on a method of

measuring and tracing water seeping from canals Previous studies at

CSU indicated that flourescent dyes could be accurately determined at

the parts per billion level The techniques developed during this study

should be useful infuture tubewell water supply and drainage studies to

be conducted in Pakistan

ii=

ACKNOWLEDGMENTS

This report was prepared by Mr W S Liang and Professor E V

Richardson of the Civil Engineering Department with the support of the

United States Agency for International Development via Contract No AID

csd-2162 Water Management Research in Arid and Sub-Humid Lands of the

Less Developed Countries The Water Management Project at CSU falls

under the general auspices of the Council of United States Universities

of Soil and Water Development in Arid and Sub-Humid Areas consisting of

the University of Arizona Colorado State University University of

California at Davis and Utah State University

iii

TABLE OF CONTENTS

FORWARD

ACKNOWLEDGMENTS

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

INTRODUCTION l 1

THEORY 1 EQUIPMENT REQUIRED 4

a Dye solution injection equipment 4

1 Mariotte vessel 4 2 Aerofeed chemical dispenser 5

b Measurement of dye concentration 5 c Samplers and containers 6 d Temperature control apparatus 6

PROCEDURE 7

a Preparation of standard solution 7 b Fluorometer calibration 8 c Preparation of injection dye solution 9 d Selection of injection rate q 10 e Injection and sampling O10 f Sample analysis and discharge computation 12

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE 13

a njection rate 13 b Sample analysis 13 c Concentration of the injected dye solution 13 d Discharge computation 13

BIBLIOGRAPHY 15

APPENDIX 16

TABLES 17

FIGURES 22

iv

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 4: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

FORWARD

This is the third technical report of a series of water management

research reports published by Colorado State University (CSU) The

report Dye Dilution Method of Discharge Measurement was supported

by funds provided by the US Agency for International Development

(AID) contract csd-2162 Water Management Research inArid and Sub-

Humid Lands of the Less Developed Countries The Water Management

Research Project isan interdepartmental effort by CSU involving the

Departments of Agricultural Engineering Agronomy Civil Engineering

Economics Political Science and Sociology

Concern of AIDWashington about the worlds agricultural production

led AID to foster the cooperation of several universities to work on research to improve water management for increased agricultural production

A consortium of universities consisting of the University of Arizona CSU

University of California at Davis and Utah State University called The

Council of United States Universities for Soil and Water Development in

Arid and Sub-Humid Areas (CUSUSWASH) was formed on May 12 1967 The

University of Arizona joined the consortium inOctober 1969 The general

chairman of CUSUSWASH isA R Chamberlain President of CSU The

Director of the Water Management Research Project at CSU isMaurice L

Albertson Professor-in-charge of the Water Resource Systems Engineering

Program inCivil Engineering

The Project has as its field of study the management of water for

the optimum development of agriculture inarid areas with special refershy

ence to the Indus Basin of Pakistan The main purposes of the Project

are to aid Pakistan and other arid and sub-humid areas in solving their

water management problems with respect to increased food production and

to cooperate with Pakistani centers of study to help them develop their

research capabilities in the areas of water management

The study reported herein on Dye Dilution Method of Discharge

Measurement was undertaken to provide information on a method of

measuring and tracing water seeping from canals Previous studies at

CSU indicated that flourescent dyes could be accurately determined at

the parts per billion level The techniques developed during this study

should be useful infuture tubewell water supply and drainage studies to

be conducted in Pakistan

ii=

ACKNOWLEDGMENTS

This report was prepared by Mr W S Liang and Professor E V

Richardson of the Civil Engineering Department with the support of the

United States Agency for International Development via Contract No AID

csd-2162 Water Management Research in Arid and Sub-Humid Lands of the

Less Developed Countries The Water Management Project at CSU falls

under the general auspices of the Council of United States Universities

of Soil and Water Development in Arid and Sub-Humid Areas consisting of

the University of Arizona Colorado State University University of

California at Davis and Utah State University

iii

TABLE OF CONTENTS

FORWARD

ACKNOWLEDGMENTS

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

INTRODUCTION l 1

THEORY 1 EQUIPMENT REQUIRED 4

a Dye solution injection equipment 4

1 Mariotte vessel 4 2 Aerofeed chemical dispenser 5

b Measurement of dye concentration 5 c Samplers and containers 6 d Temperature control apparatus 6

PROCEDURE 7

a Preparation of standard solution 7 b Fluorometer calibration 8 c Preparation of injection dye solution 9 d Selection of injection rate q 10 e Injection and sampling O10 f Sample analysis and discharge computation 12

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE 13

a njection rate 13 b Sample analysis 13 c Concentration of the injected dye solution 13 d Discharge computation 13

BIBLIOGRAPHY 15

APPENDIX 16

TABLES 17

FIGURES 22

iv

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 5: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

water management problems with respect to increased food production and

to cooperate with Pakistani centers of study to help them develop their

research capabilities in the areas of water management

The study reported herein on Dye Dilution Method of Discharge

Measurement was undertaken to provide information on a method of

measuring and tracing water seeping from canals Previous studies at

CSU indicated that flourescent dyes could be accurately determined at

the parts per billion level The techniques developed during this study

should be useful infuture tubewell water supply and drainage studies to

be conducted in Pakistan

ii=

ACKNOWLEDGMENTS

This report was prepared by Mr W S Liang and Professor E V

Richardson of the Civil Engineering Department with the support of the

United States Agency for International Development via Contract No AID

csd-2162 Water Management Research in Arid and Sub-Humid Lands of the

Less Developed Countries The Water Management Project at CSU falls

under the general auspices of the Council of United States Universities

of Soil and Water Development in Arid and Sub-Humid Areas consisting of

the University of Arizona Colorado State University University of

California at Davis and Utah State University

iii

TABLE OF CONTENTS

FORWARD

ACKNOWLEDGMENTS

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

INTRODUCTION l 1

THEORY 1 EQUIPMENT REQUIRED 4

a Dye solution injection equipment 4

1 Mariotte vessel 4 2 Aerofeed chemical dispenser 5

b Measurement of dye concentration 5 c Samplers and containers 6 d Temperature control apparatus 6

PROCEDURE 7

a Preparation of standard solution 7 b Fluorometer calibration 8 c Preparation of injection dye solution 9 d Selection of injection rate q 10 e Injection and sampling O10 f Sample analysis and discharge computation 12

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE 13

a njection rate 13 b Sample analysis 13 c Concentration of the injected dye solution 13 d Discharge computation 13

BIBLIOGRAPHY 15

APPENDIX 16

TABLES 17

FIGURES 22

iv

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 6: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

ACKNOWLEDGMENTS

This report was prepared by Mr W S Liang and Professor E V

Richardson of the Civil Engineering Department with the support of the

United States Agency for International Development via Contract No AID

csd-2162 Water Management Research in Arid and Sub-Humid Lands of the

Less Developed Countries The Water Management Project at CSU falls

under the general auspices of the Council of United States Universities

of Soil and Water Development in Arid and Sub-Humid Areas consisting of

the University of Arizona Colorado State University University of

California at Davis and Utah State University

iii

TABLE OF CONTENTS

FORWARD

ACKNOWLEDGMENTS

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

INTRODUCTION l 1

THEORY 1 EQUIPMENT REQUIRED 4

a Dye solution injection equipment 4

1 Mariotte vessel 4 2 Aerofeed chemical dispenser 5

b Measurement of dye concentration 5 c Samplers and containers 6 d Temperature control apparatus 6

PROCEDURE 7

a Preparation of standard solution 7 b Fluorometer calibration 8 c Preparation of injection dye solution 9 d Selection of injection rate q 10 e Injection and sampling O10 f Sample analysis and discharge computation 12

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE 13

a njection rate 13 b Sample analysis 13 c Concentration of the injected dye solution 13 d Discharge computation 13

BIBLIOGRAPHY 15

APPENDIX 16

TABLES 17

FIGURES 22

iv

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 7: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

TABLE OF CONTENTS

FORWARD

ACKNOWLEDGMENTS

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

INTRODUCTION l 1

THEORY 1 EQUIPMENT REQUIRED 4

a Dye solution injection equipment 4

1 Mariotte vessel 4 2 Aerofeed chemical dispenser 5

b Measurement of dye concentration 5 c Samplers and containers 6 d Temperature control apparatus 6

PROCEDURE 7

a Preparation of standard solution 7 b Fluorometer calibration 8 c Preparation of injection dye solution 9 d Selection of injection rate q 10 e Injection and sampling O10 f Sample analysis and discharge computation 12

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE 13

a njection rate 13 b Sample analysis 13 c Concentration of the injected dye solution 13 d Discharge computation 13

BIBLIOGRAPHY 15

APPENDIX 16

TABLES 17

FIGURES 22

iv

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 8: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

LIST OF TABLES

PageTable 1 Temperature-Correction Coefficients for Rhodamine WT

Rhodamine B and Pontacyl Pink Dyes 17

Table 2 Preparation of Standard Solution 18

Table 3 Calibration of Fluorometer primary filter 1-60 1 (secondary filter 23A 19

Table 4 Sample Analysis 20

Table 5 Dilution of the Injection Dye Solution 21

v

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 9: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

LIST OF FIGURES

Page Fig 1 Constant-rate-injection system 1

Fig 2 Concentration-time curve for constant-rate-injection 2

Fig 3 Concentration-time curve for sudden dump 3

Fig 4 Mariotte Vessel 4

Fig 5 Series TD parts identification 22

Fig 6 Schematic diagram of the fluorometer (from G K Turner Associates 1963 p 13) 23

Fig 7 Dilution flow chart for standard solution 24

Fig 8 Fluorometer calibration curve 8

Fig 9 Fluorometer calibration curve 25

Fig 10 Fluorometer calibration curve 26

Fig 11 (a) Dye quantities required for different discharges (C = 5 ppb) 27

(b) Aerofeed calibration 28

Fig 12 Standard form for calculating discharge 29

vi

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 10: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

INTRODUCTION

The recent development of fluorescent dyes and a fluorometer which can detect these dyes in very low concentrations has made dye-dilution methods practical for measuring discharge These methods are particularly useful for determining discharges under certain flow conditions which are unfavorable for making current meter measurements or volumetric calibrashytion Typical examples of such flow conditions are found in closed conduits ice-covered reaches and turbulent mountain streams Other applications of such fluorescent techniques might be studies of seepage losses along streams or in-place orifices or Venturi meter calibrations

The single-point constant-rate-injection method is inexpensive and easy to perform provided a sufficiently long mixing distance is available The accuracy of this method is related to the accuracy of determining the amount of dye injected the final concentration and to the dye loss in the measurement reach With equipment presently available the discharge of the injected dye is known within one percent and the concentration of the injected dye or the diluted dye can be determined to the nearest part per billion Dye loss will vary with flow conditions however with the newest WT dye the loss is so small as to be negligible under most flow conditions The techniques and a measurement example are described in the following sections

THEORY

The basic advantage of dye dilution discharge measurement is that dye can be mixed completely with water Two methods may be used for determining the discharge either in open channels or closed conduits

SDye Solution Source

Cl

Q~ Q +

- Cb -- - C2

Fig 1 Constant-rate-injection system

One method is the constant-rate-injection method and the other is the slug or total recovery method

As shown in Figure 1 the constant-rate-injection method will if the dye solution is injected constantly for a sufficient time period give

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 11: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-2shy

at a downstream point a plateau (Figure 2) on a concentration-time curve The dye concentration at the cross section of the point downstream is constant If there is not any dye loss between th injection point and the sampling point the quantity of dye measured at these two points should

0 time Fig 2 Concentration-time curve for constant-rate-injection

be the same The concentration of dye solution is defined as

cD VD -l0 VD (2-1)-VD +VW(-Ic I

cl = concentration of dye solution

c = concentration of dye

VD = volume or weight of dye

VW = volume or weight of distilled water

thus qcl + Qcb = (Q+ q)c2

S=22 q (2-2)

where q = injection rate of dye solution

Q = discharge to be measured

cl = concentration of dye solution

C2 = dye concentration at sampling point

cb = background concentration which is equivalent to the dye concentration in water before the dye solution is injected

The discharge can be calculated by measuring cl c2 cb and q

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 12: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-3-

The total-recovery method requires that the total volume of dye which is suddenly dumped into a stream be accounted for at the samplingsite At the sampling site the relation between time and the dye conshycentration is as shown in Figure 3

a 0

Ishy0

time

Fig 3 Concentration-time curve for sudden dump

Figure 3concentration-time curve for sudden dump isplotted bymeasuring the concentration at different times Based on the same reascn that the quantity of dye assuming there is no loss is the same at the injection point and the sampling point

then V1c1 = Q fo(C 2 - Cb) dt

V1c1Q = (2-3)Qo(c2 - cb) dt

where Q = discharge to be measured

V = volume of dye solution introduced into the stream

c= concentration of dye solution injected into the stream

C2 = the measured dye concentration at a given time at the sampling point

cb = the background concentration of the stream

t = time

The term f (c2 - Cb) dt is just the area under the concentration-time

curve In practice it can be approximated by

n A = Z (c i - cb) (ti+ l - ti-)2 (2-4)i =1

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 13: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-4shy

where i = the sequence number of a sample

n = the total number of samples

ti = time when a sample ci is taken

The constant-rate-injection (CRI) method is described in the following

section However it should be noted that if the concentration versus

time curve is defined for CRI method the discharge can be checked by using

equation (2-3)

EQUIPMENT REQUIRED

The following equipment is needed for CRI method

a Dye solution injection equipment

There are several kinds of devices that can be used for constantshyrate-injection Two simple operation devices are recommended

1 Mariotte vessel

The Mariotte vessel as shown in Figure 4 is so designed that the dye solution discharges through an orifice under a constant head

Airtight filler cap Air-vent tube

_initial Surface _ _

h

Reservoir

H

__lVN _____Tapered ____ end

S icDrain plug

Fig 4 Mariotte Vessel

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 14: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

- 5 -

The vessel must be airtight except for the air-vent tube At the instant the valve is opened the orifice has a head of (h + H + h) The discharge of the solution causes a partial vacuum in the space above the dye Finally a pressure equilibrium is reached when the partial vacuum plus the solution head above the tapered end of the air-vent tLbe (H)equals atmospheric pressure Then the discharge head on the orifice becomes h only After this equilibrium condition is reached air gets into the vessel from the tapered end of the air-vent tube The discharge head on the orifice does not change until the solution surface is below the tapered end of the air-vent tube The effective volume of the Mariotte vessel is the cross-sectional area times the height H Different discharge rates can be obtained by using different sizes of orifices or changing h

Discharge at more than one point may be obtained by installing the desired number of orifices in the tank The Mariotte vessel cannot be used to inject dye solushytion into a pipe with pressure in it

2 Aerofeed chemical dispenser

The TD series of Aerofeed chemical dispensers is designed to feed small quantities of liquid into pipe lines tanks or open channels at manually adjustable constant rates without the need for electric power or water pressure As shown in Figure 5 power to operate the dispenser is derived from a small quantity of compressed air The compressed air forces the liquid through a filter out through a tube into the flow meter through the flow regulator and then via a flexible plastic tube to the point of application The design of the control unit is such that a constant rate of flow is maintained at all times as long as the pressure in the tank is at least 4 to 5 psihigher than the pressure at the point of application Detailed information may be found in the Aerofeed chemical dispenser instruction manual

b Measurement of dye concentration

The fluorometer utilizes an optical bridge analogous to a Wheatstone bridge which measures the difference between light emitted by an excited sample of fluorescent material and a calibrated light path Figure 6 shows a schematic diagram of the fluorometer (GK Turner Associates 1963 p 13) The principle of operation of the fluorometer may be found in the operation manual The concentration of dye

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 15: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-6shy

solution is obtained by this device Ranges of concentration may be obtained by using different combinations of fluorometer scales and filters

c Samplers and containers

In pipe lines tubes with valve controls can be mounted at desired positions to receive the samples In open channels hand samplers are used to take the samples at several verticals As the dye

concentration may change due to the exposition of dye under light containers in dark colors are recommended

d Temperature control apparatus

Since the fluorescence of dye solution changes with temperature a constant temperature apparatus is needed in order to keep the solutions at a constant temperature during analysis This normally consists of a circulating pump heater and thermostat The temperature-correction coefficients for Rhodamine WT

Rhodamine B and Pontacyl pink dyes are given in Table 1 If

significant differences between the sample temperature and the

standard solution temperature are noted during analysis correcshy

tion factors have to be applied to obtain the correct dial readshy

ings or concentrations However if analysis of all samples

(injected dye solution cl and diluted sample c2) are made at

the same temperature no corrections need to be made

The Mariotte Vessel was made by ERCs mechanical shop the rest

of the equipment required may be ordered from several companies The major parts of this equipment are the fluorometer and the dye

solution injector The fluorometer is a Turner Ill model It can

be obtained from G K Turner Associates The dye solution inshyjector can be obtained from Aerofeed Incorporated All of the equipment is listed in the Appendix

When all the equipment is obtained two or three practice runs according to the procedures and method given in this report will give the engineer confidence in the method

All the equipment can be taken to the field when the discharge is to be measured Either battery powered inverters or a generator can be used to power the fluorometer However the recommended way which will give better results is to take all the samples and bring them back to a permanent laboratory for analysis

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 16: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-7-

PROCEDURE

a Preparation of standard solution

In order to obtain calibration curves of fluorometer dial reading versus concentration standard solutions containing known conshycentrations of dye must be prepared At least three known conshycentrations of dye solutions for each fluorometer range used must be prepared The range of concentrations needed depends on the fluorometer scale as well as the filters used

The standard solutions can be obtained by a dilution procedure based on either a volumetric process or weighing process As defined in equation (2-1)

cD VD c l D + VWbull

The flow chart for dilution is shown in Figure 7 Sample computations are given on Table 2 The volumetric dilution processes are the same as the weighing processes providing that the volume of solution is used instead of weight There is a certain relation between the concentrations by weight and by volume

WD = YDVD

WW = wVw

c CDYD VD (41 CW YDVD+YwVw (4-1)

where W = weight of dye solution

YD= specific gravity of dye solution

VD = volume of dye solution

WW = weight of distilled water

yW = specific gravity of distilled water

VW = volume of distilled water

cW = concentration of dye solution by weight

Since the volume of dye is much smaller than the volume of distilled water the specific gravity of the diluted solution can be reshypresented by yW which is 10 Thus

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 17: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-8-

CDVD ( CW YDVD + V = YDCV (4-2)

where cV = concentration of dye solution by volume

In the computation of the discharge in streams the term

C1 - C2

C2 - cb

in equation (2-2) is dimensionless therefore either cV or cW

can be used to obtain the same discharge Q Because of the precision and easy operation the weighing process is recommended

After combining the solution has to be shaken in order to get a uniform mixture Once prepared standard solutions can be stored in a dark place for a period of time

b Fluorometer calibration

Fluorometer readings are relative values of fluorescence intensity To convert readings to concentrations of a fluorescent solution the fluorometer has to be calibrated using standard solutions for each different scale The concentrations are then simply the readout on the fluorometer

Fluorescence varies linearly with concentration below several hundred parts per billion Instrument output is designed to be linear (within about one percent) with the amount of light reachshying the photomultiplier It follows that fluorometer dial readshyings vary linearly with concentration Usually a straight line can be fitted accurately by eye If there is doubt the method of least squares may be used to fit the line Most of the calibration curves are straight lines passing through origin as shown in Figure 8 At very high concentrations usually above

C0

C 0uz-

Dial Reading

Fig 8 Fluorometer calibration curve

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 18: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-9shy

several hundred ppb a curved relation may be observed It is recommended that the concentrations of samples be kept in the linear range by diluting the high concentration samples with known quantities of distilled water if necessary

The fluorometer should be calibrated immediately before the sample analysis to have consistent dial readings This is because the fluorometer may have been moved and some of the electronic components may have been touched

An example showing the calibration of the fluorometer is given on the following pages using the standard solution prepared as shown on Table 2 The calibration curves are shown on Figures 9 and 10 for scale 3x and lOx respectively

c Preparation of injection dye solution

Dye is never injected at full strength (20) into a stream or pipe but is diluted using the method described previously However because the injector has some residual dye after being used the dye solution is not diluted to an exact conshycentration but is only diluted to a concentration in the desired range The determination of the exact concentration of the injected dye solution will be described in a later section The estimated concentration of the injection dye solution may be computed as

(Q + q)c 2 (43) q

where cl = the concentration of the injection dye solution

Q = the discharge to be measured (estimated)

q = the desired injection rate

C2 = the desired concentration of the solution after mixed

The quantity of solution needed depends on the injection rate and the injection time duration The injection dye solution may be prepared approximately as follows

c1 x Ww WO = Co (4-4)

0

It is preferable to have the discharge overestimated than under estimated because a very low dye concentration is very difficult to be read on a fluorometer

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 19: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-10shy

where Wo = the quantity of known concentration of dye solution needed (inweighk)

co = the known concentration of the dye solution to be

diluted

Ww = the quantity of distilled water needed (inweight)

cl = the desired concentration of the injected dye solution (From equation (4-3))

Once c1 and Ww are determined by equation (4-3) and the time duration of the injection W can be obtained by using a certain known concentration of d9e solution Usually the original solution WT dye for example with the concentration of 2 x 108 ppb isused

d Selection of injection rate q

The injection rate is dependent on the discharge to be measured and the concentration of the injected dye solution Because low concentrations have more accurate dial readings a conshycentration of 5 ppb (c2) for the sample after mixing is recommended Figure 11 shows a chart for selecting the injection rate for c2 = 5 ppb An example is illustrated on the figure

e Injection and sampling

The general procedure for the measurement isas follows the injection rate ismeasured by a cylinder and a stopwatch before and after the test Usually the injector needs a couple of minutes to obtain a steady injection rate For a single point constant-rate injection the dye solution isusually injected at the center of a pipe or a channel

Inorder to get complete mixing the sampling point has to be a distance L (the mixing distance downstream) from the injection point The mixing distance varies with the geometryand hydraulic characteristics of the reach or pipe An equation developed by Nobuhiro Yotsukura an engineer with the US Geological Survey (written comunication 1965) may be used as a guide to determine the mixing distance in a channel The equation which is based on flume studies using a tracer solution injected in the center of the channel is given as

R 6 2yonvrgL 149 Om(45W245)

where L = the distance downstream from the dye solution injection point

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 20: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-11shy

a constant which is given as six for the point wherethe dye first comes in contact with the banks and as two for the point of complete mixing of the dye

= an empirically determined coefficient for which values have been found ranging from 03 to 08 in natural streanms but which may have values over a greater range

R = the hydraulic radius of the channel

n = the Manning roughness coefficient

g = the gravitational constant

w = the mean width of the stream

Dm = the mean depth of the stream

In a pipe line the experiments done by R W Filmer and V MYevjevich indicate that the concentration becomes uniform rapidly with distance downstream from the injection point Thedistances between the injection and sampling points depend on the accuracy of the measurement needed For more than oneinjection point the distance needed for complete mixing maybe shorter

For sampling ina pipe a single tube or several distributed tubes are used Samples taken at several points on a crossshysection by hand in a channel are required The accuracy of the measurement of the discharge in a stream is increased ifa velocity weighted sample is taken using the ETR method and a DH 48 hand sampler

Sampling time affects average dye concentration It has been shown that a two minute sampling time decreased substantiallythe error in the time-average dye concentration

The equal-transit-rate (ETR) sampling procedure first used byB C Colby in 1946 provides samples weighed for dischargedistribution The channel cross section is divided into several increments of equal width and a sampling vertical is located at the middle of each increment The number of increments depends on channel width and uniformity of velocity distribution The sampler traverses the depth at each vertical at a uniform rate from the surface to the bed and back to the surface and at the same rate in each vertical the sample volume taken fromeach vertical is proportional to the average channel discharge per unit width at that vertical All the samples from the crosssection may be mixed together to make a composite sample that represents the concentration in the cross section

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 21: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-12shy

f Sample analysis and discharge computation

The concentration of samples is determined by the relative readings on the fluorometer Standard solutions and samples in test tubes are put in a constant temperature bath The temperature in the bath should be higher than the room temperashyture Also the fluorometer should be allowed to heat up It takes one and half hours for 8he fluorometer to reach its steady temperature (approximately 96 F) Analyzing the samples under unsteady temperature will cause deviation on the relative readings

The calibration curve ismade for the fluorometer as described previously in Section b On testing the sample its conshycentration can be obtained by relating the corresponding reading on the fluorometer to the calibration curve If the temperatures of the samples are not the same as that under which the calibration curve was made temperature corrections for the concentrations as shown in Table 1 are required Since the temperature at the fluorometer is higher than that of the samples care must be taken when the readings on the fluorometer are read After putting the sample in the sample holder the fluorometer reading will reach a certain value then decrease because the fluorescence intensity of dye solutions decrease with increasing temperature The maximum steady reading for each sample is taken to determine the dye concentration of the sample

The sample of the injection dye solution is taken before or after the injection The dilution procedures of the solution are the same as described in the preparation of standard solution The diluted solution can be measured on the fluorometer and its concentration may be determined

The conputation of discharges is based on equation (2-2) where the determination of ci c2 cb and q have been discussed

previously Following is an example for the discharge comshyputation in a pipe line Also a standard form is attached (Fig 12)

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 22: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-13-

SAMPLE OF DISCHARGE COMPUTATION IN A PIPE LINE

a Injection rate

Two measurements of the injection rate were taken to make sure that the injection rate is constant

Volume of cylinder V = 90 ml

Time T = 3910 sec

T2 = 3895 sec

Average Time T = 39025 sec

Injection rate q = -90 236 lsc390 = 23062 mlsec

b Sample analysis

Sample analysis with primary filter 1-60 and secondary filter 23A is shown as Table 4

c Concentration of the injected dye solution

Table 5 shows that after dilution the solution with a concentration of 3098 x 10 C has a reading of 1820 on the fluorometer at scal8 of 3X with 10 filter The solution has a temperature of 80 F From the calibration curve (Fig 9)the concentration Cz = 981 ppb then

3098 x 105C = 981

981 C1 = 981 ---5-= 316660 x 10 ppb

3098 x 10

d Discharge computation

Discharges are computed as follows and enter in column (11) of Table 4 for sample analysis The concentrationsof the injectiondye solution cl was obtained as 316660 x 10 ppb from equation (2-2)

2 -b qCq

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 23: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-14-

Substituting all the figures into the equation

Q2-3 = (316660 shy1680 shy

=Q2-e (316660 shy1194 shy

Q2-9 = (316660 shy1065 shy

Q2_12= (316660 shy1093 shy

where

1680198

1194217 )

10653011

109313831

1 cfs = 2831685 mlsec

23062 1740 cfs2831685

23062 2640 cfs2831685

23062 3375 cfs2831685

23062 = 3632 cfs2831685

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 24: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-15-

BIBLIOGRAPHY

1 Aerofeed Incorporated Aerofeed Chemical Dispenser Instruction Manual Aerofeed Incorporated IB-TD-3

2 Ellis W R A Review of Radioisotope Method of Stream Gauging Review paper Journal of Hydrology 5 1967 pp 233-257

3 Filmer R W and V M Yevdjevich The Use of Tracers in Making Accurate Discharge Measurement in Pipelines CSU Report CER66RWF-VMY38 1966

4 Guy H P Field Methods for Measurement of Fluvial Sediment Techniques of Water-Resources Investigation of USGS Book 3 Chapter C2

5 Kilpatrick F A Flow Calibration by Dye-dilution Measurement Civil Engineering - ASCE February 1968 pp 74-76

6 Turner Associates Operating and Service Manual - Model 111 Fluorometer G K Turner Associates

7 United States Geological Survey Measurement of Discharge byDye-dilution Method Hydraulic Measurement and Computation Book 1 Chapter 14 1965

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 25: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-16-

APPENDIX

The equipment required is listed as follows Both the cost and the place to order them are indicated

a Turner Model 111 Fluorometer

G K Turner Associates 2524 Pulgas Avenue Palo Alto California

Cost (without any additional unit) 1970 $168500

b Aerofeed Chemical Dispenser TD

Aerofeed Incorporated PO Box 303 Chalfont Pennsylvania 18914

Cost 1969 $ 33500

c Heater Circulation pump Thermometer

Fisher Scientific Company E H Sargent amp Co and other industrial suppliers

Cost Heater Circulation pump Thermometer

$1000 $4000 $ 500

d Thodamine WT dye 20 by weight

E I Dupont Wilmington Delaware

Cost 1970 $ 210 per lb

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 26: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-17-

Table 1 Temperature-Correction Coefficients for Rhodamine WT Rhodamine B and Pontacyl Pink Dyes

Temperature Temperature-correction coefficient

Difference (Ts - T) [Fdeg] Rhodamine WT Rhodamine B Pontacyl Pink

-20 136 135 138

-15 125 125 127

-10 116 116 117

- 8 113 113 114

6 109 109 110

- 5 108 108 108

- 4 106 106 107

-3 105 105 105

- 2 103 103 103

- 1 102 102 102

0 100 100 100

+ 1 099 099 098

+ 2 097 097 097

+ 3 096 096 095

+ 4 094 094 094

+ 5 093 093 092

+ 6 091 091 091

+ 8 089 089 088

+10 086 086 085

+15 080 080 079

+20 074 074 073

bullTs = the standard curvette-sample temperature

T = the curvette-sample temperature at the time the sample was tested in the fluorometer

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 27: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

S Flask No

(2) Flask Wt

gm

(3) Water Gross Wt

gm

(4) Water Net Wt

gm

Table 2 Preparation of Standard Solution

(5) (6) (7) (8)Dye Sol Flask Wt Dye Sol Wt of New Gross Wt gm Net Wt Solution

gm gm (4)+(7) gm

(9) Dilution Factor

7ppb(8

(0) C C2 = (9)xCI

ppb

1 0 990000 990000 49260 38550 10710 1000710 1070x10-2 2x10 8 2140x10 6

2 0 990000 990000 49158 38385 10773 1000773 1076x10-2 2140x106 2303x104

4 0 1980000 1980000 59067 38381 20686 2000686 1034x10-2 2303x104 238097

5 0 800000 800000 88280 91670 87159 88129

38452 38494 38501 38604

=

4S828 53176 49658 49525 202187 1002187 02017 238097 48035

7 0 930000 930000 88311 58857

38421 38419

z =

49890 20438 70328 1000328 00703 238097 16735

8 0 800000 800000 89174 87286 87512 88858

38054 38020 38005 38026

51120 49266 49507 50832

z= 200725 1000725 02006 48035 9635

3 0 900000 900000 88833 87772

37966 38035

Z=

50867 49737 006 1000604 01005 48035 4830

11 0 750000 750000 88128 38059 50069 800069 00626 48035 3010

Weighing scale was set on zero when the flasks were weighted

-18shy

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 28: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-19-

Table 3 Calibration of Fluorometer Isprimary filter 1-60AI secondary filter 23A)

Fink(2) Concentration

No ppb

(3) Temperature

OF

(466ri~~ Scale FIl

Reading

7 Average

Dul Itube 80 3x 10 0 0

7 16735 80 3x 10 3640 3660

3650

8 v635 80 3x 10 1650 1690

1670

3 4830 80 3x 10 560 540

550

11 3010 80 3x 10 180 240

210

Dull tube 80 lOx 10 1000 1000

7 16735 80 lOx 10

8 9635 80 lOx 10 5300 5320

5310

3 4830 80 lOx 10 2460 2440

2450

11 3010 80 lOx 10 1280 1240

1260

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 29: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

Table 4 Sample Analysis

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Sample No

Dial Reading

Average Fluoro Scale

Filter

Sampler Temp

Concent C2

Sampling Time

Temp Correction

C2 After

Discharge Q

Remarks

OF ppb sec Correction cfs

ppb

2-1 610610 610 lOx 10 80 198 100 198 Backshyground

2-3 35503540 3545 3x 10 80 1680 120 100 1680 1740

2-4 730710 720 lOx 10 80 217 100 217 Backshyground

2-6 23402360 2350 3x 10 80 1194 120 100 1194 2640

2-7 12801260 1270 lOx _ground

10 80 301 100 301 Backshy

2-92-9 20402040 2040 3x 10 1

80 1065 120 100 1065 3375

2-10 16001600 1600 lOx 10 80 383 100 383 _ground

Backshy

2110 2110

2110 3x 10 80 1093 120 100 1093 3632

-20shy

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 30: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

Table 5 Dilution of the Injection Dye Solution

-T -- F F-- -4)Flask Flask Wt Water Water (5) (6) (7) (8) (9) (10)Dye Sol Flask Wt Dye Sol (11)No Wt of New Dilutiongm Gross Wt Net Wt Gross Wt gm C1 C2 = (9)xCINet Wt Solution Factor ppbgm ppbgm gm gm (4)+(7) 7

13 0 780000 780000 77126 55334 21792 801792 2178xi0- 2 C1 2178xlO-2C14 0 780000 780000 68749 38411 30338 810338 3744x10- 2 2178xlO-2C 10176x10- 3C15 0 780000 780000 44535 20042 24493 804493 3045x10- 2 10176xlO- 3C 3098xlO-5 C

C1 = Concentration of the injection dye solution

-21shy

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 31: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-22-

Filling

Air Bleed Tubing

Air Bleed Valve

Regulator Body

Rate Control Assembly Nut

Rate Control Valve

Metering Tube

Metering Tube Guard

BallI Float

Meter Housing

Jack Screw Nut

Flow Shut-Off

Valve 3 111

J4x - Bushing

Filter (inside tank)

Cap Air Seal Valve Tank Pressure Gage- uk ont

Quick Connect Pump Coupling

Mounting Bracket -

-= Regulator Air Hose

Outlet

Storage Tank

1 Air Pump

0

Discharge Tubing

Fig 5 Series TD parts identification

I

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 32: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-23-

Blank Knob

PhotoultillerFluorescencePhotouttilierDial

tBlank 0Boa-Light Interrupter htr

- -- ~-~- Light Cam

bullMounting Block eol -bull - v LII1~f Diffuse Lucite Light Ms Diffuse

4- ScreenPipes-

s--Forword Li Poath

= - Far - Ultraviolet

Lamp

Filter (Secndary) Range Selector

t C Sample Filter Four Apertures Motor Cooling Fan (Primary) ( IX 3X IOX 30X)

Figure 6 Schematic diagram of the fluorometer (from G KTurner Associates 1963 p 13)

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 33: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-24-

Rhodamine Wt Dye Solution Co = 20 =z xl0 8 ppb

B Concentration of Solution B

Cbx = Co 10 gm Solution A ioe

10 gm Solution A + 990gmn DistiledWoe = Z XlO6ppbIgmB

Cc =Cbx IOgm(B)+990gm(DW)

2X10 6 X 10 2 X104 ppb

1000

IOgm(C Cd = C x Ogm(c)+990gm(DW)c

200ppb

125gm(D) 75g(D) 50lm(D)Ce = Cd x 25g(D) +7gm(D)+4gm(DW) Cg= Cd XSOgm(D)+425gm(DW)

50 ppb 30 ppb =_20ppb

k m 4gm(E) L 5gm(I k = =Ce x 4Ogm(E)+460gmDW) C C1 x 50gm(I) + 450gm(DW)

4ppb = I ppb

Fig 7 Dilution flow chart for standard solution

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 34: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-25shy20

18shy

16shy

14-

12-

Scale 3xTemperature

Filter 10

800 F

0shy

8

6shy

4

2 0 10

Fig

I I 20 30 40

Dial Reading

9 Fluorometer calibration curve

50 60

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 35: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

-26shy0

0

0 0LL

xe le - 0

_0

0

-0

C

0 ro

0

-0

COID I 0_ (qdd) uojjDJjua3uoO3

Fig 10 Fluorometer calibration curve

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 36: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

(a) Dye quantities required for different discharges (C = 5 ppb)

-Of I2 C(j

0o -11 0000110C -4DCdeg A___ shy

204 0 40 60 80 0 0 400 60

Estimated discharge in stream to be measured by dye dilution method (cfs) Example Estimated stream discharge is 35 cfs required injection (C = 04) Note Different aerofeed tanks mayrate is therefore about 124 misec which requires that ball setting have different calibrations

on rate meter on aerofeed tank needs to be about 25 at this rate and each should be determinedif the tank has 8 liters of dye approximately 18 hours of continuous injection is available before the tank is empty

Fig 11

0

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 37: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

4

(b)

Total

Aerofeed

injection2

calibration

time available 1O

in hours Q08 06

Bail 10

reading on 20 30

flow 40

rate meter 50 60 70 80

60 90100

-- W- 20-O-

E

400

10

08shy

06-

2shy

04_

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy

Page 38: INTERNATIONAL DEVELOPMENT FOR AID USE ONLY BIBLIOGRAPHIC INPUT SHEET

DateDYE DILUTION DISCHARGE MEASUREMENT ON GH = at (start) Avg wii-h= ft Depth I DYE INJECTIO

at _ (finish) Approx Q =

MGH = _ cfs

Party

(a)Time when started (c) Rate

(b) Conc of C =

II COLLECTION AND ANALYSIS OF MEASUREMENT SAMPLES Avg Sampling Sample Time Est Partial Fluorometer Analysis

section No Sampled Discharge Scale Dial Readings

- misec Weighted Dial Readings (3)x(5)

and dist (1) (2) (3) (4) (5) (6) below pt of inject Background

=Weighted Mean Dial Reading (6V(3) =

Net Dial Reading = WMDR - Avg Background Dial Reading =C2

CIII PREPARATION OF SPECIFIC STANDARDS FROM

(a) General Serial Dilution Equation Cn = (Va + )Ci = DF x C1

(b) Anticipated Dye Conc in Stream C2 = 353x10 5 C1shy

(c) Working Standard (usually the second

serial dilution)

Ci = CB = 1O C= ppb

the initial concentration(d) Letting C2 be the desired new conc Cn and CB

Ci compute (Va + Vi) for different values of estimated discharge

Stand Est Result (Va + Vi) = ACTUAL DILUTIONS Total FLUOROMETER ANALYSIS Dilution cale Readings NetNo C2 i Va Vi - Vi

a i + Factor Readings(cfs) (ppb) C Va i X 10- 5 C1 __

Cc

CD _

CE ___

Distilled water or water used in dilutions same

IV COMPUTATION OF ACTUAL DISCHARGE 5 o - Net reading for standard of C

1 Q = 353 x 10 q (2= 353 x 10 q Total dilution factor Net dial readingC2

Fig 12 Standard form for calculating discharge

-29shy